Behelden

If the current version causes so many conflicts with other plugins and themes, maybe reverting back to the prior version is the best course.

I don’t suppose there’s a straightforward way to acquire the older version of the plugin?

Nice work! FYI, I spotted an error though. Went to the event calendar page and got this:

Fatal error: Call to undefined function contenteventscalendar() in /data/9/1/42/57/1205383/user/1284541/htdocs/wpfiles/wp-content/themes/default/page.php on line 22

I had the same problem. (Incidentally if you’re using AWStats this totally screws with your stats–it showed that I had 20,000 or so hits in a couple minutes).

What worked for me was to delete my wp-admin and wp-includes directories (making backups first!) as well as just about every file from my root directory (I only had my sitemaps and config file left), then re-downloading and re-installing a fresh copy of 2.5.1.

Not mind blowingly clever, but it worked.